THORACOSCOPIC MANAGEMENT OF SPINE TUMORS

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1 1. Introduction: THORACOSCOPIC MANAGEMENT OF SPINE TUMORS 3. Surgical Procedures: 81 Endoscopic surgical techniques are used in many disciplines after its first usage in gastroenterological interventions. It has come into market in spinal surgery especially following its use in pulmonary surgery (1-3). Thoracoscopic management of spine tumors are first performed by Raffenberg in 1981 and published in 1990 (4). Meanwhile, it is practiced in many clinics all over the world, though not so widespread yet. Recently, endoscopic procedures are succesfully performed for the management of spine tumors (1,2,3,5). Endoscopic approaches should be chosen for appropriate cases if the surgeon has adequate experience. Endoscopic approaches are also performed to paraspinal pathologies. 2. Indications and Contrindications: The general indications and contrindications of thoracoscopy and thoracal spine tumors are available for thoracoscopic spine tumor approaches and written in chapter 4b. Primer spine tumors can be managed easily with endoscopic approaches. They generally arise from the osseous and cartilage tissues. Especially, the osteoid osteoma and osteoblastoma and other osteoid based tumors and sarcomas can be excised with thoracoscopic approaches. Although it is rare, biopsy and/or total excision of thoracal cordomas and primer paraspinal soft tissue tumors can be achieved via endoscopy. Except metastatic tumors such as prostate, lung, breast and renal carcinomas, the lymphomas and multipl myelomas can also be excised with endoscopic approach. 3.a. Surgical equipment: The instruments of thoracoscopic spine surgery are similar with routine thoracoscopic surgery instruments and they also defined in chapter 4b. 3.b. Operating room set up: The surgeon is positioned at the right or left side according to the pathology and the assistant is located opposite to the surgeon. While the anesthesia team is located at the head of the table, the nurse is at the right side of the surgeon. The monitors of endoscopy and scopy must be positioned at the opposite side of the surgeon while the scopy is located at the foot of the operating table (figure 1). 3.c. Patient Positioning: The patient is positioned in left or right lateral decubitis position depending on the localisation of the pathology after the induction of general anesthesia (Figure 2). The patient is covered after staining and marking of the thoracar entrance localizations. 3.d. Surgical Technique: The preoperative surgical planning is important especially to arrange the working channel of the endoscope. The general tendency is to perform the working channel on the projection of the pathology in front of the midaxillar line with a pathological view. The bone grafts and/or cages are performed via these windows. However, the working windows just on the pathology are needed with a right angle to the pathlogy, if the instrumentation is necessary.

2 82 Thoracoscopic Management of Spine Tumors Figure 1: Operating room set up is shown. The number and localization of the incisions depend on the level of the pathology on the vertebral column. One of the incisions for trochar enterance is for the light source and one for lung ecartation. A third incision is placed on the mid axillary line or slightly behind it to access directly to the vertebral corpus (figure 3a). Anatomically, there is difficulty for the lesions of the Th1-4 th vertebrae and those caudal to the Th11 th vertebra. If instrumentation is planned, the incision must be right at the mid axillary line. But where access to the spinal cord is mandatory, the incision must be anterior to this line. Thus, the spinal canal will be under control entirely. Trochars are manipulated through small incisions on the thoracal wall. After entering to the thoracal cavity, with the help of fluoroscopy, the vertebral level is defined and the pleura is incised. As a general rule, the pleura which is on the pathology is incised after arriving to the thorax cavity. After incising the parietal pleura, the capsule at the head of costovertebral joint is incised and costovertebral articulation is excised so that access to the vertebral body from side is possible. Because the costovertebral articulation adheres to the intervertebral disc, the upper edge of the caudal vertebral body and the lower edge of the cranial vertebral body (figure 3b). The segmentary artery and vein at the pathologic vertebral level are identified and cautherized. The distal end of this artery is cut at the point of enterance to the foramen, and the proximal end is cut close to its exit from the aorta. Cautherising the distal end in the foramen deeply may disturb the arterial anasthomosis feeding the spinal cord. The excision of costovertebral joint increase the working area and provide to control the lower and upper disc levels. The tumor tissue can be excised totally, because of its soft characteristics. The cartilage endplates of the upper and lower vertebrae must be protected to avoid from the spreading to the closer structures especially in metastatic tumors (Figure 3c,d). The posterior wall of the vertebrae comprise the anterior all Figure 2: The drawing of the patient positioning is shown.

3 lectasis after operation. For these reason, to control the blood gase levels and urine output of the patient is important after operation. Because of the speciality of surgery, prophylactic antibiotics should be used. The costae are not broken in thoracoscopic endoscopy, so the postoperative pain is less than classical approches. The patient do not need more analgesics and can be mobilized in the first day after postoperative care unit. Daily PA chest graphies may provide the early diagnosis of athelectasis and possible infection. 83 Figure 3a: The localization of the working channels and insertion of the ports is showing. of the spinal canal with strong structure called as posterior longitudinal ligament. It will better to change the drilling tip with dimond one when we come closer to posterior wall of vertebrae. While working in this area, using the multidirection kerrison rongeurs with long shaft may decrease the operation time. If the tumor has a sclerotic structure, high speed drills can be used. After the tumor resection, hemosthasis of the operation area is performed. The bone grafts insertion can be performed to the tumor resected area (Figure 3e). The appropriate spinal implants can be constructed to maintain the stability of the thoracal vertebrae after the resection of the tumor (Figure 3f). A 32-Fr chest tube is inserted to avoid from atelectasia and hemothorax before closing the pleura, subcutaneous and cutaneous tissues. 4. Postoperative Care: The patients stay at the postoperative care unit in first day. The major possible problem is the continuing athe- Figure 3b: The excision of the costovertebral articulation is showing.

4 84 Thoracoscopic Management of Spine Tumors 5. Complications and Avoidance: Generally, the parcial or total vertebrectomy with tumoral resection may cause to major bleeding. For this reason, the chest tube must be located after operation. Complications of this procedure are: atelectasis, gross hemorrhage, pulmonary injury, spinal cord injury, tension pneumothorax (6). This techique needs a step learning curve. Tactile feedback for the surgeon is impossible during this surgery. A pulmonary surgeon is generally needed to attend to the session. A perfect three dimension visualization during discectomy is impossible. Multiple stab incisions for trochar incisions, perhaps one more for ecartation of incompletely collapsed lung, and a retractor for the diaphragm are all considered to be the unfavorable points for this surgery. The preparations for conventional thoracotomy must be completed before thoracoscopic procedures for major complication occurence. 7. References: 1. Al-Sayyad MJ, Crawford AH, Wolf RK. Early experiences with video-assisted thoracoscopic surgery: our first 70 cases. Spine. 2004; 29(17): Rosenthal D, Dickman CA. Thoracoscopic microsurgical excision of herniated thoracic discs.j Neurosurg. 1998; 89(2): Mack MJ, Regan JJ, Bobechko WP, et al. Application of thoracoscopy for diseases of the spine. Ann Thorac Surg. 1993; 56(3): Raffenberg M, Mai J, Loddenkemper R. Results of thoracoscopy in localized lung and chest wall diseases. Pneumologie Feb;44 Suppl 1: Case Illustrations: Case 1: A 40 year-old woman, admitted to our department with complaints of back pain and dyspnea for one month. The history of the patient revealed a right breast carcinoma one year ago and she was accompanying a 7 year old dialysis. The radiological images of the patient showed mass at the corpus of Th5 vertebra (Figure 4a,4b). The metastatic mass of the thoracal vertebra body was resected via thoracoscopic approach. After the resection of the tumor, thoracal implant was located to the resection of the mass to avoid from the spinal instability (Figure 4c,d). Figure 4a,4b: T2 weighted sagittal and axial MRI scans showing the mass located at the Th5 vertebra body. Figure 4c,4d: The anteroposterior and lateral thoracal graphy is showing the implant.

5 5. Kuklo TR, Lenke LG. Thoracoscopic spine surgery: current indications and techniques. Orthop Nurs. 2000; 19(6): Theodore N, Dickman CA. Thoracoscopic approaches to the Spine. In Winn HR(ed): Youmans Neurological surgery. Philadelphia, Saunders 2004; 4: Figure 3c: The photo is showing the opening of the paravertebral structures. Figure 3d: The photo is showing the tumor resection located at the vertebra body. Figure 3e: The photo is showing the insertion of bone graft. Figure 3f: The photo is showing the insertion of the thoracal implant.